Additives for diesel (and petrol) engines have been available for years and you will hear arguments for and against. I heard about adding some 2 stroke to diesel when filling up and read about it here.
http://www.freel2.com/forum/topic878.html
I have a 1998 2.5 td Ducato and I decided to give it a try about three years ago. After a few weeks it seemed to make a difference to the engine, quieter and seemed to have a bit more power. I have been adding it ever since to every fill. Engine has 100k miles up now and seems to be going better than ever !
Have a read and make up your own mind !
http://www.freel2.com/forum/topic878.html
I have a 1998 2.5 td Ducato and I decided to give it a try about three years ago. After a few weeks it seemed to make a difference to the engine, quieter and seemed to have a bit more power. I have been adding it ever since to every fill. Engine has 100k miles up now and seems to be going better than ever !
Have a read and make up your own mind !